Headlight tester



R. N. FALGE Jan. 24, 1939.

HEADLIGHT TESTER Filed Nov.

24, 1934 4 Sheets-Sheet l Jan. 24, 1939. R FALGE 2,144,838

HEADLIGHT TESTER Filed Nov. 24, 1934 4 Sheets-Sheet 2 awe/WM Jan. 24,1939. R N FALGE 2,144,838

HEADLIGHT TESTER Filed Nov. 24, 1934 4 Shets-Sheet s Jan. 24, 1939.FALGE 2,144,838

HEADLIGHT TESTER Filed Nov. 24, 1934 1 Sheets-Sheet 4 Zhwentor 90%(Ittcrnegs Patented Jan. 24, 1939 2,144,838 nmnuen'r 'rns'ma Robert N.Falge, Anderson, mama to General Motors Corporation, Detroit, Mlcln, acorporation of Delaware Application November 24, 1934, Serial No.154,562

21Clalms.

This invention has to do with equipment for testing a headlamp todetermine whether it is functioning efficiently, whether the filament orother light source is in proper position with respect to the. focus ofthe reflector, and whether the headlamp is properly aimed down the road.

The apparatus consists essentially of a supporting structure which ispreferably designed to be mounted on the headlampand which carries thetesting device which incorporates condensing lenses for projectingimages of the beam on a screen rigidly connected to the lens holder andspaced but a foot or so in front of it. The testing apparatus isadiustably mounted on. the supfrom selected parts of the lamp, and oftenthese 1 bundles of rays have been subject to errors which make themunrepresentative of the beam as a whole, This typeof error is avoidedin. the present construction by intercepting substantially all rayswhich might be directed into the upper part of the beam.

Another advantage of lenses resides in the fact that the images on thescreen are of such brilliance owing to the condensing action of the lensthat they can readily be seen in daylight 'without resorting to cowlingof the screen.

One of the above described devices is prefer- 0 ably provided for eachof the headlamps, and each is equipped with meansto receive a bar,extending crosswise of the vehicle to locate the horizontal axes throughthecentersv of the faces, of both lamps in a plane substantially atright angles to the longitudinal axis of the vehicle.

I have also preferably incorporated in the testing equipment means formeasuring the intensity of the light from some part'of the image. Thismay take several forms, but I prefer to simply slot the screen at thecenter "of the image, and arrange behind it'some type of light measuringinstrument, preferably a photoelectric, light sensitive cell equippedwith an indicating ammeter. The readings of the ammeter arenot onlyhelpful I in determining whether the' light output ofthe a furthermodification.

lamp is as good as it should be, but also in affording an indication ofwhether or not the bulb is properly focused inthe headlamp.

' Many variations will occur to those skilled in the art, and for acomplete description, reference is made to the accompanying drawings.

Figure l is a perspective view showing a pair of headlight testersmounted on headlamps as they would appear in, the final stages of thetest. Figure 2 is a side elevation, partly in section, m of one of thetesters. Figure 3 is a section on line 3-3 of Figure 2.

Figure 4 is a section on line 4-4 of Figure 1. .Figure 5 is aperspective view of the spacing cylinder of Figure 4. r

Figure 6 is a section on line 6-6 of Figure 2. Figure 7 is a-section online 1-1 of Figure 2. Figure 8 is a detail of the supporting frameshowing the lamp rim engaging side.

Figure 9 isa section taken on line 9-9 of m Figure 8.

Figure 10 is a fragmentary view showing a modified form of target.

Figure 11 is a perspective view of a further modification of target. 3

Figure 12 is a front'elevation of, another modification of target. I

Figure 13 is a fragmentary side elevation show- 7 ing a furthermodification of target. I

Figure 14 is a view. similar toFlgure 13 showing In the preferred formof the invention. the testers are supported by the lampsthemselves.However, in cases where it would not befeasible to clamp'the devices onthe lamps, the construc- 35 tion could beequipped withsup'portsextending tubemay beclamped inplaceby tightening bolt 45 1a; Figure 6. jBa 16 is hollow and within its rear end slidably reeeivesa collar 20having inte-v gral therewith a downwardly and sidew'ardly ex-, tending1arm 22 to the lower end of which is piv'oted'a frame i4 carryingdownwardly extend- ,ing clamping fingers 26 adapted to engage the rearend of the lamp housing. The upper part ofmember 24 'is aperture'd'toreceive an adJu'st-' ing screw 28 having a knurled end to enable it a tobeeasily manipulated. The endof theI-adthe member l6 so that by rotatingthe screw '28 the member 24 with its fingers 25 may be swung toward orfrom the lamp housing. In the specific construction illustrated theinner end of screw 28 bears against the head of bolt 38 which passesthrough an aperture in collar 28 and engages a threaded passage inanchoring stud 32 which passes through alined holes in the member [6.The bolt 38 serves to hold the member 28 in place.

Supporting frame l8 likewise carries at its upper portion a bearing 34and at its bottom portion a bearing 35 in which is mounted for rotationonly an adjusting screw 38. This screw has right and left hand threadedportions. The upper threaded portion 38 is received in a threadedaperture in a yoke 48 carrying two spaced fingers 42 adapted to engagethe top of the headlamp at either side of its center line. The bottomthreaded portion 44 is received in a threaded aperture in a yoke 46carrying fingers 48 adapted to engage the bottom of the headlamp housingon either side of the center line. Fingers I2, 26, 42 and 48 arepreferably covered with some kind of relatively soft material such asfiber to prevent scratching of the headlamp housing. The space in thecenter of the screw 38, between the two threaded ends, is covered withrubber, or other soft material, to accommodate heavily convex lenseswhich are too deep to contact fingers l2.

With the construction described it will be apparent that by adjustingthe screw 28 the headlamp is clamped between the fingers l2 and thefingers 26, and by adjusting the screw 38 the. headlamp is clampedbetween the fingers 42 and' vided at their ends with suitable nuts andlock nuts. The frame 54 carries lenses 88 and 82. Each of the lenses isin the form of a horizontal cylindrical prism. The lower lens 88 is thelarger, and is of sufficient width and depth to en-- compasssubstantially the entire portion of the light from the headlamp thatforms the top of the beam. This light comes from the central horizontalzone of the headlamp in conventional constructions. The smaller lens 82is'for use in aiming old-style, single-beam headlamps in which the lightwhich forms the top of the beam may come from near the top of theheadlamp.

It will be noted from Figure 3 that the screen bears at its upperportion a reference line 84, and at its lower portion areference line 88at either side of which are located parallel limit lines 88. Referencelines 84 and 88 are used in aiming the beam. Limit lines 88 are used infocussing the beam. As shown in Figure 3, I have provided anaperture 88at the centerof and with its upper edge on referenceline 88, behindwhich is alight sensitive cell I85 connected to micro-ammeter 98.

I The cell converts the light into electrical energy,

andthe amount of the energy is measured by. means of micro-ammeter 58. Ihave, preferred to locate the opening 88 in the position shown becausehere the two hot spots from the sides of output of the headlamp, butalso upon the accuwith an upwardly extending bifurcated arm 18,

arranged to receive threaded rod 14' which is fixedly secured tosupporting frame l8 and which carries nuts 12 for clamping the testingdevice in any desired position with reference to the lamp face. Throughthis means, the level of the beam pattern on thescreen may be adjustedreadily with reference to reference lines 64 and 68.

Upon the member 14 is slidably mounted a cylindrical member 16 havingapertures 18 about its periphery. One end of these apertures is adaptedto,receive pin 88 which serves to lock thecylinder against rotation onstud 14. The different apertures are provided with spacer pins ofdiflerent length. By drawing the cylinder out and rotating it, any oneof these spacers 82 may be made to register against pin 88. Thesespacers serve to limit the inward movement of adjusting nut 12 andpermit the mechanic to pre-set the angle of the testing device 58 withreference to the supporting frame l8. One aperture is left without aspacer such that the cylinder may slide to its the angle of the testingdevice by definite steps,

say one-half degree apart. In use, the device would be supplemented by alist of the different headlamps and the spacer to be used with each. Thespacer length for a given headlamp would be such that the beam patternon the screen would register within substantially one quarter of onedegree of the correct 'level when all of the optical parts were incorrect adjustment. Up and down focussing inaccuracies of headlamps ofconventional design would be'evidenced by deviations in the level of thetop of the lower beam pattern from reference line 58. Should the upperlevel of the beam pattern fall outside limit lines 68, it would indicatethat the light source was too inaccurately located up and down to beacceptable. In the case of a fixed-focus headlamp, the recourse is toreverse the bulb in the socket or try a different one. headlamps, thesame procedure may be followed as in the previous sentence if, aftermoving the bulb ahead and back until the beam pattern is properlyconcentrated, the top of the pattern still falls outside the limitlines. In the case of headlamps with double-focussing mechanisms, theprocedure would be that of first concentrating the pattern with theaxial focussingscrew and then adjusting it to the correct level with thevertical focussing screw.

The lens carrying frame 54 is provided at the bottom with forwardlyprojecting bearings 84 adapted to receive tie bar 88. When tie bar 88 isin the position shown in Figure 1, the axes of the headlamps lie invertical planes substantially parallel to the vertical plane through thelongltudinal axis of the vehicle.

The apparatus so far described is sufiicient for focussing the headlamp,but not for aiming, since the lamp, the supporting frame, and thetesting In the case of single-focus typedevice will function to testfocussing whatever be the angle of the lamp axis to the horizontal. Topermit aiming, I have provided on each of the devices a-llquid level 96.This level is preferably supported on two adjusting nuts 'iilll mountedon threaded studs 98 fixedly secured to one of the supporting rods 58.As shown in Figure 2, the adlusting nuts are held against rotation bymeans of pivoted dogs I02 yieldingly urged into notches in the edges ofthe nuts by springs I04. By adlusting one of the nuts lllll up or down,the angle of the level 96. with reference to the horizontal may beadjusted as desired. I prefer to establish the pitch of the threads andthe space between adjusting nuts so that the adjusting nuts may bedivided into twelve equal parts, each part representing a change ofangleof one inch in twenty-five feet.

I prefer to use the nut Ill, nearest the target. to compensate forvariations from the true horizontal in the floor on which the vehiclestands. By calibrating the pitch of the floor in each adjustment stallin terms of inches at twenty-five feet and marking the value on the rearwall of the stall, or other convenient plade, it is a simple matter toduplicate the setting on the level adjusting nut and thereby refer thebubble in the level to the level of the floor on which the vehiclestands.

I prefer to use the nut III, nearest the headlamp, to pre-set the liquidlevel for the angle at which it is designed to aim the top of the beamabove or below the horizontal. For-example,

with the dog IM registering in notch marked II,

the top of the beam would be horizontal when the Operation The mechanicfirst polishes up the reflectors.

cleans the lenses, replaces blackened bulbs and eliminates highresistance contacts in the electrical circuit.

He then lowers the testing device over the lamp and clamps it roughly inposition between pads l2 and rods l2, l8 and 26. He then rotates thedevice about the lamp axis until threaded rod 38 is parallel with thevertical flutes on the lens.

Thereafter, he clamps the device securely in position by tighteningscrews 28 and 36.

He then adjusts the testing device ill about pivots 52 by means ofadjusting nuts 12 until the light sensitive cell shows a maximum readingon the meter. If means is provided for moving the bulb ahead and back inthe reflector, he adjusts the bulb ahead and back until the meterreading is a maximum. If no cell is provided, he merely adjusts the bulbahead and back until the hot spot is as bright as possible and the beampattern is of minimum depth.

He then notes the make and type of lamp and determines the proper stud82 from a table of values. He registers that stud over pin .0 and clampslocknuts l2 andlens carrying frame 54 securely in position against it.This presets the testing device in such manner that with accurateoptical parts accurately aligned in the lamp,

the top of the beam pattern would register on reference line 68.

He then notes the degree of deviation of the top of the beam fromreference line 66. If the lamp incorporates a vertical as well as anaxial focussing mechanism, he adjusts the bulb up or down until the topof the beam pattern registers on reference line 68. He then readjuststhe axial focussing mechanism until the meter reading is' amaximum. ii

If the lamp incorporates only an axial focussing mechanism and thedeviation exceeds limit lines I, he may turn the bulb over in thesocketor try another bulb repeating the entire operation described in thethree paragraphs above. The same would be true in the case of a lampwhich incorporates no focussing means, except that in I this case themeter reading should be noted for each bulb tried and an effort made toselect a bulb which results in a high reading.

'I'he'beam pattern is next examined for defects.

Excessive stray light above the hot spot usually means that thereflector is inaccurate. Hazy and indeflniteihot spots usually'indicateafrosted lens.

loosens up nuts 12, rotates the cylinder I6 until the blank apertureregisters on pin 80 and slides the cylinderback as far aslt will go. Hethen adjusts nuts I! until the top of the beam pattern registers on lineand locks the test device in that position.:v Should the upper patternexten'd above reference line I, as sometimes happens with old stylesingles-beam headlamps when the light source is above focus, a furtheradjustment in the angle of the test device is needed to register the topof that pattern on its line, letting the top of the lower pattern dropbelow reference line 66.

The mechanic then loosens up each of the headlamps at the universaljoint ordinarily provided for the purpose. He inserts tie-bar 86 throughbearings N on the testing device support. Insertion of the tie-bar isfacilitated by'rocklng and rotating one headlamp while slipping thetie-bar through the bearing. This automatically locates the flutes onthe headlamps in the vertical plane and lines up the axes of theheadlamps in vertical planes parallel to the vertical plane through thelongitudinal center lineof the vehicle. It presupposes that asymmetricalbeam headlamps such as are described and claimed in Falge and GodleyPatent No. 1,929,1l1, granted October 3,- 1933, will be produced withsuflicient accuracy to insure proper aim sideways when the axis of thelamp is aimed straight ahead. It restricts movement of the headlamps tothe one vertical plane, thereby facilitating adjustment. However, ifdesired, the connection between the test heads,ancl the tie bar 86 maybe such as to permit sldewise as well as up anddown adjustment of thelamps to allow for variations in lateral aiming of' asymmetric whetherthe rear seat is usually loaded and the characteristics of the driver.

The final step consists in rocking the lamps forward or backward intheir mountings until the bubbles are centered in the levels and thenlocking the lamps in position. This is best done by first setting up onelamp lightly with the bubble approximately centered, then setting up theother lamp securely with the bubble accurately centered, and thensetting up the first lamp securely with the bubble accurately centered.

This completes the adjustment, operation.

The light sensitive cell has the further possibility, when supplementedby'a list of ratings on different types of lamps, that it"may be used tocheck the efllciency. of the lighting system. A low reading may indicatea reflector which has the silver polished off, a defective bulb, afrosted lens, a high resistance in the electrical system due to a poorcontact or a poor ground, or a discharged or defective battery.

For best results, in some respects, the cell aperture 88 in the targetis unfortunatelyplaced in that it interferes with observation of theentire beam pattern. There are several variations which lookinteresting.

One variation is shown in Figure-10. Here, the aperture 88 may be leftin its present position,

the target 200 painted black, its entire face covered with a diffusingsheet 28! of paper or other material which both reflects and transmitslight,

the reference lines to be marked on this diffusing i mined relation tothe lamp axis, said guideways sheet, the whole to' be covered andprotected against dirt and grease by a sheet 202 of transparent materialsuch as glass or pyralin. In such a case'the entire beam pattern wouldbe visible but the amount of light which reaches the cell through thediffusing screen would be substantially reducedsand the meter would haveto be more sensitive.

Another alternative would be that of providin a supplementary metaltarget 288 with the ref-- erence lines on it as shown in Figure 11,arranged to cover the aperture "when in position and to swing out of theway or be removed when a cell used in aimingto measure-the quantity ofstray light above the hot spot and hold the value down to certainlimits. I Instead of aperture 88 in the target, a removable mirror 2I8might be used to reflect the light on the cell at some point between thelens holder and the target asshown in Figure 13. In such a case, theslot would have to be at the same distance from the lenses as thetarget. Or the cell might be pivoted or otherwise movable, as shown at2|! in Figure'14 so that it could be swung into position ahead of thetarget. In the latter case, however, a special cell would be neededwhich would locate thelight sensitive diaphragm close to the target andthereby avoid error due to deviation from the focal point of lenses and82. In any event, the light which reaches the cell would have to bescreened to provide the equivalent of slot Q8.

In other respects, the described apparatus is of such size as to receiveonly a portion of the lamp axes are in predetermined relation to eachcapable of considerable modification in practice.

when used on a car assembly line, the device could be simplifiedsubstantially since it would have to handle only one type and sizeoflamp. In such a case, the lamps might be assembled to, the device as aunit and the whole swung into position on the car after focusslng andaiming with reference to each other. The assembly operation would thenconsist merely in bolting the two lamps to their supports with thebubble centered in the level.

I claim:

1. In headlamp testing apparatus, the combination of condensing lensmeans of suificient sizeto encompass a large portion of the light fromthe center and sides of the headlamp, a screen, means for supporting thescreen, substantially at the focus of the lens means to receive the beampattern image projected thereby, said screen being freely exposed toview and having an opening centrally located in the beam patternreceiving portion thereof, and a photometer associated therewith havinga light sensitive element arranged behind the opening, said openingbeing image prolectedfrom the center of said headlamp and from adjacentportions of the sides of the headlamp so that the light intensityreading of said photometer will indicate separation or approach of thebeams projected from the sides of the headlamp and consequently theaccuracy of focusing of the light source in the headlamp.

2. Headlamp aligning apparatus comprising a pair of guideways, means foradjustably securing each of the guideways to a headlamp in"predeterbeing arranged on said securing means so as to be aligned whensosecured with the headlamp axes in predetermined relation to eachother, and a'guide member adapted to be slidably received in saidguideways when so aligned so as to hold them in aligned position.

3. In headlamp testing apparatus the combination of a pair of headlamptesting devices. means for adjustably securing each of said devices to aheadlamp in predetermined relation to the lamp axis, each of saiddevices including a guideway arranged to be in lateral alignment withthe guideway of the other device when the other, and a guide memberadapted to be slidably received in said guideways when-so aligned so asto hold them in aligned position.

4. In a headlight testing apparatus the combination of a support, a testhead comprising an unobstructed focusing lens and a screen spaced fromthe lens arranged to receive the image projected by the lens, saidscreen being exposed to view, means for mounting the test head on thesupport for pivotal adjustment about an axis at right angles to the axisof the lens, a level mounted on the test head and arranged with its axisparallel to the axis of the lens, and means for adjusting the angle ofthe level in a plane at right angles to the axis of movement of the testhead, said last-named means comprising independently adjustablesupporting devices engaging opposite ends of the level and adapted to beindependently adjusted to tilt the level to compensate for differentfactors affecting aiming of the lamp.

5. In a headlight tester, the combination ofa lens holder, a condensinglens in the holder, a

screen substantially at the focus of the lens. spaced struts connectingthe holder and screen in 1 spaced relation and exposing the screen toview from all sides, and a level adjustably mounted on one of saidstruts.

6. In a headlight tester, a screen having 2. reference mark thereon,means for supporting the screen in spaced relation in front of one ofthe vehicle headlamps, a level arranged with its axis extending towardthe screen, and means for mounting the level on saidsupporting meanscomprising independent vertically adjustable supporting devices engagingopposite ends of the level and arranged to be independently adjusted totilt the level in a vertical plane to compensate for different factorsaffecting aiming of the lamp.

7. In the combination as defined in claim 6, said last-named deviceseach comprising two parts having adjustably threaded engagement witheach other, one of said parts rotatably engaging one end of the level,while the other part is secured to the said supporting means, and meansadapted to engage said first-named part to hold it in adjusted position.

8. In a headlight tester, a test head comprising a screen, a lensholder, an unobstructed condensing lens in the holder, struts connectingthe screen and the holder in spaced relation with the. screen at thefocus of the lens, said screen being exposed to view from substantiallyall sides, a level, and means for mounting the level on one of saidstruts comprising independent vertically adjustable supporting devicesengaging opposite ends of the level and adapted to be independent- -lyadjusted to tilt the level in a vertical plane to compensate fordifferent factors affecting aiming of the lamp.

9. In the combination as defined in claim 8, said last-named deviceseach comprising two parts having adjustably threaded engagement witheach other, one of said parts rotatably engaging one end of the levelwhile the other part is secured to the said supporting means, and meansadapted to engage said first-named part to hold it in adjusted position.

, 10. In a headlight tester, thecombination of a screen having acalibration mark thereon, a

condensing lens, a skeleton frame connecting the lens and screen withthe screen positioned at the, focus of the lens, said frame permittingready inspection of the screenfrom all sides, said lens being ofsuflicient size to encompass a substantial portion of therays from theheadlamp and being unobstructed'so as to reproduce on the screen reducedin size but increased in intensity a considerable part of the beampattern projected by the .headlamp, a level, and means for mounting thelevel on said frame comprising independent verlenses mounted in saidholder, each of said lenses being of sumcient size to'encompass a largeproportion of the rays of light from an automobile headlamp, said lensesbeing of substantially the same focal length and being arranged withtheir axes substantially parallel, a screen arranged substantially atthe foci of said lenses, a frame rigidly connecting the holder andscreen but freely exposing the screen to view, and means for adjustablysupporting the testing device in front of an automobile headlamp withthe lenses overlying the headlamp and the screen spaced forwardlytherefrom. and with the optical axis of the testing device substantiallyalined with the optical axis of the headlamp.

12. In the combination as defined in claim 11, one of said lenses beingarranged above the other and encompassing the major portion of the lightfrom the upper portion of the headlamp.

13. In the combination as defined in claim said lenses making contactwith each other'along one of the edges thereof, and being of suificientarea together to encompass the greater portion of the light from aheadlamp.

14. In a headlight tester the combination'of a pair of rigid plates,rods connecting said plates adjacent their margins and holding them infixed parallel relation, one of said plates being apertured, acondensing lens mounted in said aperture of such focal length as tobring the rays passing therethrough to a focus on the other plate, saidlast-named plate having indicia thereon, threaded studs mounted in oneof said rods and extending vertically upward, nuts threaded on saidstuds, a level having its opposite ends supported by said nuts, andmeans for yieldably holding the level in engagement therewith;

15. In the combination as defined in claim 14 said last-named meanscomprising a tension spring connecting the level and the rod betweensaid studs.

16. In a headlight tester the combination of a support, a condensinglens mounted on the support, a light pattern receiving and displayingdevice, a light measuring device, means for mounting one of said deviceson the support so as to have its light receiving portion adjacent thefocus of the lens, and means for movably mounting the other of saiddevices on said support for movement between an operative position withits light receiving part in advance of the light receiving part ofthefirst-named device and adjacent the focus of the lens and an inoperativeposition out of the path of the light rays.

17. In a headlight tester the combination of a support, a condensinglens mounted on the support, a screen mounted in said support formovement between an operative position at the focus of ed on the supporton a horizontal transverse pivot, said test head comprising a frame, afocusing lens and screen mounted on the frame in spaced relation, withthe screen substantially at the focus of the lens, said lens being ofsufficient size to encompass a large portion of the light from aheadlamp so as to reproduce at its focus an image of a large portionofthe beam pattern, said frame being constructed so as to freely exposethe screen to view, said screen having an opening therein in the portionthereof receiving the beam pattern but of substantially less area thansaid pattern, and a photometer having its light sensitive elementarranged behind said opening.

19. In headlight testing apparatus the combination of a support, a testhead pivotally mounted on thesupport on a horizontal transverse pivot,said test head comprising a frame,

a focusing lens and screen mounted on the frame in spaced relation, withthe screen substantially at the focus of the lens, said lens being ofsufflclent size to encompass a large portion of the light from aheadlamp so as to reproduce at its focus an image of a large portion ofthe beam pattern, said frame being constructed so as to freely exposethe screen to view. a level mounted on the frame with its axis extendingsubstantially parallel to the axis of the test head so as to determinethe tilt of the projected beam, said screen having an opening therein inthe portion thereof receiving the beam pattern but of substantially lessarea than said pattern, and a photometer having its light sensitiveelement arranged behind said opening. v

20. In a headlight tester, a lens holder having a converging lenstherein adapted to encompass the central zone of a headlamp so as toreceive substantially all of the light forming the top of the beam, ascreen arranged adjacent the focus of the lens so as to receive theimage projected thereby-and being freely-exposed to view, meansconnecting the lens holder and screen in fixed relation, said lens beingunobstructed so that substantially all of the light from said centralzone is condensed by it on the screen, said screen having an aperture inthe portion thereof receiving said image, said aperture being ofsubstantially less area than the image, a light measuring device havinga light sensitive element,

said tester includinrmeans for supporting the 5 light measuring devicewith its light sensitive element exposed in said aperture and facingsaid lens.

21. The combination of unitary supporting means for a headlamp testercomprising a clamp- 10 ing member adapted to engage the front of aheadlamp, a clamping member adapted to engage the rear of the headlamp,means adjustably connecting said members to enable them to be movedtoward each other to clamp a headlamp between 15 them, spaced adjustableclamping means support- ,ed' by one of said clamping members adapted toengage the headlamp on either side of its longitudinal axis to centerthe supporting means with respect thereto, means for adjusting saidlast- 80

